Controlling The Stirrer - OHAUS Guardian 7000 Serie Installations-, Betriebs- Und Wartungsanweisungen

Guardian 7000 Series

2.3 Controlling the Stirrer

1. Rotate the right knob (D) to control the speed setting
(R).
a) Clockwise rotation will increase the speed
setting (R).
b) Counterclockwise rotation will decrease the
speed setting (R).
2. To turn on the stirrer, press and hold the right knob
(D) until the unit beeps and the stirrer indicator (Q)
illuminates.
a) The unit will beep once to confirm the stirrer
has been turned on.
b) The stirrer indicator (Q) will illuminate next to
the "RPM" symbol to indicate that the stirrer is
running.
c) The timer (T) will begin counting up from
00:00, or down from a set time.
d) The actual stir speed (P) will be displayed in
the top right region of the screen.
3. To change the speed setting while the stirrer is on:
a) Rotate the right knob (D) to the new speed
setting.
The speed setting (R) will blink to indicate that
the speed setting is not confirmed.
b) Briefly press the right knob (D) to confirm the
new speed setting.
The speed setting (R) will stop blinking once
the new setting is confirmed.
Note: If the speed setting (R) remains idle without
confirmation for 4 seconds, it will reset to the
current setting
4. To turn off the stirrer, press and hold the right knob
(D) until the unit beeps and the stirrer indicator (Q)
disappears.
a) The unit will beep once to confirm the stirrer
has been turned off.
The stirrer indicator (Q) next to the "RPM"
b)
symbol will disappear to indicate that the
stirrer is off.
c) The timer (T) will reset back to 00:00 or the
previous timer setting.
If the heater is still running, then the timer will
continue to count.
STIRRING OPERATING TIPS
The stirrer increases speed at a steady rate until the setpoint is reached. If the stirrer is not reaching its setpoint: 1)
the stir bar may be too large, 2) the liquid may be too viscous, 3) the setpoint speed may need to be reduced.
Additionally, the magnetic strength of stir bars reduce over time and may need to be replaced.
When heating and stirring a reaction vessel within an oil bath or similar set-up, the stirring function will stir up to
approximately one inch (2.5 cm) from the top plate. The stirring speed will vary according to liquid viscosity, spin
bar length, and distance from top plate. Adjust one or all of these to achieve the desired stirring speed. For
example: the closer the reaction vessel is to the top plate, the strong the magnetic connection between the unit and
the stir bar.
EN-11